title: On the effect of calcium antagonists on cerebral blood flow in rats. A comparison of nimodipine and flunarizine.
abstract: To assess the influence of nimodipine treatment in brain tissue at different levels of blood pressure, we estimated the cerebral blood flow using hydrogen clearance. Rats were treated with nimodipine (n = 8), its placebo (n = 10), flunarizine (n = 11) and its placebo (n = 10), and a group of controls (n = 10). Cerebral blood flow was estimated during arterial normo-, hyper- and hypotension. The lowest cerebral blood flow estimates calculated for nimodipine were 43.8 +/- 7.8, 90.9 +/- 13.3, and 33.6 +/- 6.1 ml/min/100 g for normo-, hyper- and hypotension, respectively. Cerebral blood flow in the nimodipine placebo group was 84.1 +/- 10.3, 139.9 +/- 19.9, and 55.2 +/- 10.5 ml/min/100 g. In the flunarizine group, the blood flow was 77.3 +/- 15.2, 144.7 +/- 15.0, and 43.8 +/- 5.9 ml/min/100 g. In the control group, cerebral blood flow was 90.0 +/- 29.1, 143.0 +/- 42.1, and 75.5 +/- 29.8 ml/min/100 g. The low blood flow in the nimodipine group might have been a consequence of brain edema caused by extravasates. Thus impaired blood flow reduces the usefulness of nimodipine in the prevention of vasospasm. Flunarizine is a potential alternative treatment of vasospasm treatment as well as for cerebral blood flow improvement, as shown in our experimental study.
authors.affiliation: Neurosurgical Clinic, Hannover Medical School, Fed. Rep. of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Zumkeller
authors.forename: H E
authors.initials: HE
authors.lastname: Heissler
authors.forename: H
authors.initials: H
authors.lastname: Dietz
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D001794:Blood Pressure / Q000502:physiology; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002560:Cerebrovascular Circulation / Q000187:drug effects* / Q000502:physiology; D005444:Flunarizine / Q000494:pharmacology*; D009553:Nimodipine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D002121:Calcium Channel Blockers; D009553:Nimodipine; D005444:Flunarizine